1. Field of the Invention
The present invention relates to an apparatus and method for preventing free flow during enteral or parenteral administration solutions through an infusion line. More particularly, the present invention relates to an occluder/valve and method of use for infusion sets and the like, wherein the occluder/valve prevents undesirable free-flow of solution through the infusion set while allowing controlled flow through the infusion set.
2. State of the Art
The use of infusion sets to administer solutions to patients is well known in the medical arts. Infusion sets are used for both enteral and parenteral applications. Enteral feeding pumps are used to provide patients with nutrition and medication when they are unable, for a variety of reasons, to eat normally. Parenteral (intravenous) solutions are provided to patients to ensure adequate hydration and to provide needed nutrients, minerals and medication. Often, the infusion set is placed in a free standing arrangement in which gravity forces the solution into the patient. The rate at which the solution enters the patient can be roughly controlled by various clamps, such as roller clamps, which are currently available on the market.
In many applications, it is necessary to precisely control the amount of solution which enters the patient. When this is the case, a regulating device, such as an enteral feeding pump, is placed along the infusion set to control the rate at which the solution is fed to the patient. In applications where a pump, etc., is used, the clamps used to regulate flow are typically opened to their fullest extent to prevent the clamp from interfering with the proper functioning of the pump. The clamp is opened with the expectation that the enteral feeding pump will control fluid flow through the infusion set. However, emergencies or other distractions may prevent the medical personnel from properly loading the infusion set in the enteral feeding pump.
When the infusion set is not properly loaded in the pump and the clamp has been opened, a situation known as free-flow often develops. The force of gravity causes the solution to flow freely into the patient unchecked by the pump or other regulating device. Under a free-flow condition, an amount of solution many times the desired dose can be supplied to the patient within a relatively short time period. This can be particularly dangerous if the solution contains potent medicines and the patient""s body is not physically strong enough to adjust to the large inflow of solution.
Numerous devices have been developed in an attempt to prevent free flow conditions. Such devices, however, typically add significantly to the overall cost of the infusion set and some provide only marginal protection against free flow.
Thus, there is a need for a device that prevents a free-flow condition while allowing controlled flow through the infusion set. There is also a need for such a device which prevents free-flow if an infusion set is not properly mounted in a pump or other regulating means.
It is an object of the present invention to provide an apparatus and method for occluding infusion sets to prevent an accidental free-flow condition.
It is another object of the present invention to provide an occluder which is simple to make and use.
It is another object of the present invention to provide such an occluder which is inexpensive and thus disposable.
It is still another object of the present invention to provide an occluder which occludes fluid flow through the infusion set unless the infusion set is properly loaded in a flow control mechanism such as an enteral feeding pump.
It is still yet another object of the present invention to provide such an occluder which allows for a simple manual override of the occluding function.
It is still yet another aspect of the invention to provide an occluder which functions as a valve to effectively control fluid flow through a flexible conduit.
The above and other objects of the invention are realized in an apparatus and method for preventing free flow in an infusion set. In accordance with one aspect of the invention, an occluder is disposed within the infusion set. The occluder is configured to prevent free flow of fluids in the infusion set past the occluder. The occluder is also configured, however, selectively to allow solutions to pass by the occluder which are pumped by an enteral feeding pump and the like.
In accordance with one embodiment of the invention, the occluder is formed by a stop placed in the tubing of the infusion set. The stop limits flow around and/or through the stop when the solution is subject to flow due to gravity. However, when greater pressures are placed on the solution, such as those produced by a pump, the solution is able to flow around and/or through the stop, thereby delivering the solution to the patient.
In accordance with another embodiment of the present invention, an occluding valve is disposed in the infusion set. The valve prevents free flow through the infusion set due to gravity, while allowing controlled flow of solution through the infusion set.
In accordance with another aspect of the invention, the occluder is configured to stop fluid flow until the infusion set has been properly loaded into a control mechanism such as a pump. Once properly placed, the interaction between the occluder and the infusion set effectively opens the infusion set to allow solution to flow therethrough.
In accordance with still another aspect of the present invention, the occluder can be formed integrally with the infusion set or can be formed of independent piece(s) which are then placed in the infusion set to selectively occlude the flow of solution therethrough.
In accordance with still yet another aspect of the invention, the occluder can function as a valve to selectively allow fluid flow therethrough. In one embodiment, a pair of occluders and infusion line can be used in conjunction with a piston or other force applicator to form a linear peristaltic pump which delivers predetermined amounts of fluid to a patient.
In accordance with still yet another aspect of the present invention, the occluder and infusion line can be formed to nest in and be opened by a conventional fluid flow pump.